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Control.OnKeyUp Method

Raises the KeyUp event.

[Visual Basic]
Protected Overridable Sub OnKeyUp( _
   ByVal e As KeyEventArgs _
)
[C#]
protected virtual void OnKeyUp(
 KeyEventArgs e
);
[C++]
protected: virtual void OnKeyUp(
 KeyEventArgs* e
);
[JScript]
protected function OnKeyUp(
   e : KeyEventArgs
);

Parameters

e
A KeyEventArgs that contains the event data.

Remarks

Raising an event invokes the event handler through a delegate. For more information, see Raising an Event.

The OnKeyUp method also allows derived classes to handle the event without attaching a delegate. This is the preferred technique for handling the event in a derived class.

Notes to Inheritors:  When overriding OnKeyUp in a derived class, be sure to call the base class's OnKeyUp method so that registered delegates receive the event.

Example

[Visual Basic] 
' This example demonstrates how to use the KeyUp event with the Help class to display
' pop-up style help to the user of the application. When the user presses F1, the Help
' class displays a pop-up window, similar to a ToolTip, near the control. This example assumes
' that a TextBox control, named textBox1, has been added to the form and its KeyUp
' event has been contected to this event handling method.
Private Sub textBox1_KeyUp(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles textBox1.KeyUp
    ' Determine whether the key entered is the F1 key. Display help if it is.
    If e.KeyCode = Keys.F1 Then
        ' Display a pop-up help topic to assist the user.
        Help.ShowPopup(textBox1, "Enter your first name", New Point(textBox1.Right, Me.textBox1.Bottom))
    End If
End Sub 'textBox1_KeyUp

[C#] 
// This example demonstrates how to use the KeyUp event with the Help class to display
// pop-up style help to the user of the application. When the user presses F1, the Help
// class displays a pop-up window, similar to a ToolTip, near the control. This example assumes
// that a TextBox control, named textBox1, has been added to the form and its KeyUp
// event has been contected to this event handling method.
private void textBox1_KeyUp(object sender, System.Windows.Forms.KeyEventArgs e)
{
    // Determine whether the key entered is the F1 key. Display help if it is.
    if(e.KeyCode == Keys.F1)
    {
        // Display a pop-up help topic to assist the user.
        Help.ShowPopup(textBox1, "Enter your first name", new Point(textBox1.Right, this.textBox1.Bottom));
    }
}

[C++] 
// This example demonstrates how to use the KeyUp event with the Help class to display
// pop-up style help to the user of the application. When the user presses F1, the Help
// class displays a pop-up window, similar to a ToolTip, near the control. This example assumes
// that a TextBox control, named textBox1, has been added to the form and its KeyUp
// event has been connected to this event handling method.
private:
void textBox1_KeyUp(Object* /*sender*/, System::Windows::Forms::KeyEventArgs* e)
{
   // Determine whether the key entered is the F1 key. Display help if it is.
   if(e->KeyCode == Keys::F1)
   {
      // Display a pop-up help topic to assist the user.
      Help::ShowPopup(textBox1, S"Enter your first name",
         Point(textBox1->Right, this->textBox1->Bottom));
   }
}

[JScript] No example is available for JScript. To view a Visual Basic, C#, or C++ example, click the Language Filter button Language Filter in the upper-left corner of the page.

Requirements

Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family, .NET Compact Framework

See Also

Control Class | Control Members | System.Windows.Forms Namespace | KeyUp

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